U.S. Pat. No. 5,642,605 discloses a food portion inventory system which employs a series of plastic food storage bags. The bags have a flap at 16 and a rear panel portion 12 which cooperate to provide closure.
U.S. Pat. No. 7,806,595 discloses a deli bag and stack which has adhesive strips at 32 which secure the bags in the stack and also provide closure.